Live stream viewable while sending and receiving text in group and among groups

A streamer terminal (102) makes (122), upon receiving text, the text appear in a screen, determines (123) whether a streamer pays attention to the text, until the text exits from the screen, and executes (124) a predetermined attention process on text-of-attention that the streamer is determined to pay attention to. Each terminal (103) of viewer terminals classified into any one of groups transmits (132) text accepted from a viewer using each terminal to the streamer terminal (102) and another viewing terminals (103) belonging to an identical group, receives (133) text transmitted from another viewer terminal belonging to the identical group, and makes (134) the text appear in a screen. The streamer terminal (102) transmits (124) the text-of-attention to viewer terminals (103) classified in another group, and each terminal of the viewer terminals (103), upon receiving the text-of-attention, makes the text-of-attention appear in the screen.